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Why does the OFS diagnostics window show "Asynchronous write2 rejected for group ##TSEventsGroup##"?

Issue
The message Error: Asynchronous write2 rejected for group ##TSEventsGroup## (client #: client domain) (uid: #) can show on the OFS log that the customer doesn't follow some best practices.

Product Line
Vijeo Citect, CitectSCADA, OFS

Environment
CitectSCADA 2018, OFS 3.62

Resolution
A reserved OPC group name is to be used at group creation for a TS event process and the default name is '##TSEventsGroup##'. The OFS can return E_FAIL detected error if one of the operations below are performed:
IOPCGroupStateMgt: SetName()
IOPCGroupStateMgt: CloneGroup()
any OPCSyncIO method
any OPCSyncIO2 method
write by a nonstandard group

A variable used as TS can't be written, because this group is exclusively for subscribe event sources and to operate Synch or Asynch R/W an item must be part exclusively of a "Standard" OPC group. If you see the message below on the OFS log, the first step is to look for write command for TS variables on your SCADA application and remove it.
"02/02 11:35:01 428ms : Error : Asynchronous write2 rejected for group ##TSEventsGroup## (client 11 : SDSC-SERVERP\Administrator) (uid: 27659)”